-LRB- CNN -RRB- Spain is officially clear of Ebola , the World Health Organization declared Tuesday , after no new cases were reported since a nurse 's assistant who contracted the virus there tested negative for it .

Since then , 42 days have passed -- double the maximum known incubation period for the virus -- without another case , allowing Spain to be declared free of Ebola .

Spanish authorities had been monitoring 87 people who came into contact with healthcare worker Teresa Romero Ramos , 15 of whom were considered high-risk and were quarantined at a Madrid hospital , WHO said .

Another 145 hospital employees who helped care for Romero during her month-long stay at the Carlos III Hospital were also monitored .

The WHO statement said it `` commends Spain for the measures put in place to identify potential cases and prevent further transmission of the Ebola virus . ''

Romero contracted the illness while helping to care for an infected missionary who had been brought back from West Africa . He died of the disease .

CNN 's Anna Maja Rappard contributed to this report .

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Spain is declared Ebola-free by the World Health Organization

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There have been no new cases since a nurse 's aide recovered from Ebola in October

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Spanish authorities had been monitoring scores of people who had contact with her